This invention relates to an apparatus and method for aligning rail ends for welding.
Railway tracks as is well known include a pair of parallel spaced rails mounted on ties at an accurate pre-determined spacing or gauge so that the rolling stock can run along the rails. Each rail has an upper rail head on which the wheel runs and a flange or base which engages the ties, together with a web of reduced transversed dimension inter-connecting the base and the head. Since the early development of rails, these have been supplied in finite lengths each of which is separately attached to the ties and is coupled to the next adjacent length with a spacing to accommodate expansion of the rails. There are many thousands of miles of such rails presently laid and in use in Canada and in other countries.
It has long been known that the junctions between the rail lengths cause excessive vibration on the wheels and rolling stock which rapidly causes wear and damage to the rolling stock. Programs have therefore recently been undertaken to weld the adjacent rail ends together to form effectively a continuous rail thus eliminating the characteristic and damaging vibration of the rolling stock crossing the junctions. The welding technique has become well established and uses what is known as a thermite weld which is a chemical welding technique obtained by placing a mold around the adjacent rail ends in which a chemical welding technique takes place.
However, techniques for accurately aligning the rail ends prior to welding are generally very crude. These include manual wedging of the rails at the required location prior to the attachment of the mold for the thermite weld. Specifically designed devices are available for aligning the rail ends but these are complex, expensive and difficult to use and have therefore met with little success.